Welcome to Sol Gateway

The Gateways are space stations that serve as ports of entry for inhabited star systems. Not all star systems have a Gateway, but all of the homeworld systems do. Here is the description of Sol Gateway from The Octopod Prisoner:

The gateway had begun its existence as an asteroid mining operation in a comma-shaped asteroid on the outer edges of the Solar system. Like any piece of real estate, its location had proved critical to its desirability for other purposes — specifically, with the development of a practical faster-than-light drive, a need had arisen for a space port of sorts. It had to be far enough out to serve as a point of arrival and departure for ships that punched far above their weight, gravitationally speaking, but close enough for trade and defense purposes. The station’s traffic controllers ensured that ships departing for destinations in-system stuck to carefully delineated velocities and flight paths designed to minimize the environmental impact of ships whose velocities could bend space. For defense, the Terran Fleet maintained a visible and well-provisioned base of operations at Sol Gateway, as a tacit warning to any enemies, and the best communications network humans could devise, in order to mount a rapid response to any threat.

So the played-out mine on the comma-shaped asteroid was abandoned; the asteroid itself became little more than the anchorage for a series of interconnected habitats that grew until the asteroid was enclosed by seven stacked sets of rings, with the second ring from the top, encircling the largest bulge of the “comma,” with one smaller ring above, and five progressively smaller rings below. Arriving ships were assigned a parking orbit around the Gateway; traders offloaded their cargo onto barges that hung like strings of hexagonal beads in orbit around the station. Likewise, ships picking up cargo did so from those same barges.  On any given circadian day, as many as one hundred ships might arrive or depart from the station, representing all four species: the flattened discs of the gu’ul ships; the submarine-shaped human ships with their two doughnut-shaped gravitic drive housings; the avian ships, like fat-bellied birds in flight, encircled by two sets of flattened, swept-back wings; and the octopod ships, long ovals encircled by an intertwined eight-armed lacework that kept them from being crushed as their velocities approached and then exceeded natures’ preexisting speed limit.